a(n) = round((5^n)*4 / 3^n).

Terms

a(0) =4a(1) =7a(2) =11a(3) =19a(4) =31a(5) =51a(6) =86a(7) =143a(8) =238a(9) =397a(10) =662a(11) =1103a(12) =1838a(13) =3063a(14) =5104a(15) =8507a(16) =14179a(17) =23631a(18) =39386a(19) =65643a(20) =109404a(21) =182341a(22) =303901a(23) =506502a(24) =844170a(25) =1406950a(26) =2344917a(27) =3908195a(28) =6513658a(29) =10856097